Beam splitter/combiner with path length compensator and method for making the same

Abstract

A beam splitter/path length compensator assembly for use in a color imaging assembly, comprising a beam splitter for splitting a polychromatic imaging light beam into a plurality of color component beams, and an integrally formed, transparent path length compensator device for differentially adjusting the focus distances of the color component beams. The beam splitter is encased within the path length compensator device. A color imaging assembly utilizing the beam splitter/path length compensator assembly for forming spatially separated, color component images of an object on a unitary image plane is also disclosed. A method for producing a beam splitter/path length compensator assembly is also disclosed. An optical assembly utilizing a beam combiner/path length compensator assembly for spatially and spectrally combining a plurality of color component optical beams into a combined optical beam having a unitary optical axis is also disclosed.

We claim: 
     
       1. A beam splitter/path length compensator assembly for use in a color imaging assembly comprising: beam splitter means for splitting a polychromatic imaging light beam into a plurality of color component beams;   integrally formed, transparent path length compensator device comprising a path length compensator means for differentially adjusting the focus distances of said color component beams;   said beam splitter means being fixedly encased within said path .length compensator device without application of adhesive to said path length compensator device in regions thereof which are intersected by said imaging light beam.   
     
     
       2. The invention of claim 1, said path length compensator device comprising a molded plastic device, said beam splitter means comprising a planar glass surface directly interfacing with a surface portion of said molded plastic device whereby stresses on said planar glass surface of said beam splitter means which are associated with adhesive attachment of said planar glass surface to an adjacent surface of a path length compensator with a separate adhesive medium are obviated. 
     
     
       3. A beam splitter/path length compensator assembly for use in a color imaging assembly for forming spatially separated, color component images of an object on a unitary image plane, said beam splitter/path length compensator assembly comprising: a) beam splitter means having a plurality of parallel, color component beam reflecting layers disposed obliquely in the path of a polychromatic light beam for splitting said polychromatic imaging light beam into a plurality of parallel, spatially and spectrally separated, color component beams having optical axes positioned perpendicular to said unitary image plane;   b) a unitary, integrally formed path length compensator device comprising: i) beam splitter housing means for securely, nonadhesively holding said beam splitter means in fixed relationship with said unitary image plane and for spatially separating said beam splitter means from said unitary image plane; and   ii) path length compensator means disposed between said beam splitter means and said unitary image plane for refractively compensating for differences in optical path lengths of said plurality of color component beams, whereby each of said color component beams provides a focused color component image of said object on said unitary image plane.     
     
     
       4. The invention of claim 3, said beam splitter housing means comprising a cavity, said cavity comprising a bottom wall, a first sidewall, and a second sidewall, wherein said beam splitter is partially encased within said cavity and is securely, compressively held within said cavity. 
     
     
       5. The invention of claim 3, said beam splitter housing means comprising a cavity, said cavity comprising a bottom wall, a top wall, a first sidewall, and a second sidewall, wherein said beam splitter is fully encased within said cavity and is securely, compressively held within said cavity.